Transdermal fentanyl for postoperative pain management in patients recovering from abdominal gynecologic surgery

The current placebo-controlled double-blinded study was undertaken to assess the safety and efficacy, as well as the potential clinical role, of the transdermal therapeutic system (TTS) of fentanyl delivery in the postoperative setting. TTS patches releasing 25 μg · h^-1 or 50 μg · h^{- 1} or placebo were applied to 95 women 1 h before abdominal gynecologic surgery during general anesthesia. Postoperatively, patients self- administered intravenous morphine as required using patient-controlled analgesia with a 1-mg incremental dose and a 6-min lockout interval. Each was assessed upon admission to the postanesthesia care unit and at intervals over the following 72 h with respect to vital signs, visual analogue scale pain and satisfaction scores, side effects, and cumulative morphine use. Data were analyzed using analysis of variance, Kruskal-Wallis, and chi-square. P < 0.05 was considered significant. There were no demographic differences among groups. Beginning 32 h after TTS application, a statistically significant morphine-sparing effect was seen with the 50 μg · h^-1 patch. There were no significant differences among groups with regard to visual analogue scale pain scores at rest, patient satisfaction, or the incidence of side effects; a significant reduction in pain upon movement was noted at 24 h in patients treated with TTS 50 μg · h^-1. This finding constituted the only benefit noted with this form of analgesic therapy in the present investigation.